The present invention generally relates to the field of devices such as pressure washers and the like that are capable of delivering a fluid from a supply source and discharging it at a greater pressure, and more particularly to a high pressure pump suitable for use in such devices having an integral start valve.
High pressure washing devices, commonly referred to as pressure washers, deliver a fluid, typically water, under high pressure to a surface to be cleaned, stripped or prepared for other treatment. Pressure washers are produced in a variety of designs and can be used to perform numerous functions in industrial, commercial and home applications. Pressure washers typically include an internal combustion engine that drives a pump to which a high pressure spray wand is coupled via a length of hose. Pressure washers may be stationary or portable. Stationary pressure washers are generally used in industrial or commercial applications such as car washes or the like. Portable pressure washers typically include a power/pump unit that can be carried or wheeled from place to place. A source of water, for example, a garden hose, is connected to the pump inlet, and the high pressure hose and spray wand connected to the pump outlet.
Wherein the internal combustion engine utilized to provide power to the pump includes a pull starter that is manually pulled by a user to start the engine, it has been found that the engine may be difficult to start since because the pump must pump water during the start stroke of the engine, thus, making the pull starter difficult to pull. Consequently, it would be desirable to provide a high pressure pump suitable for use in devices such as pressure washers or the like, wherein the pump""s head assembly includes an integral start valve for allowing the fluid through the head assembly so the engine may be more easily started.
Accordingly, the present invention is directed to a high pressure pump suitable for use in devices such as pressure washers, or the like, wherein the pump""s head assembly includes an integral start valve for allowing the fluid being pumped to circulate through the head assembly while the engine powering the pump is started. In an exemplary embodiment, the pump includes a pump assembly for pumping the fluid so that its pressure and/or flow rate are increased and a head assembly for porting the fluid to and from the pump assembly. The head assembly includes an inlet portion suitable for receiving a supply of the fluid and an outlet portion suitable for outputting the liquid received from the pump assembly. A start valve assembly disposed in the head assembly circulates fluid within the head assembly from the inlet portion to the outlet portion bypassing the pump assembly as the engine powering the pump is started. When the pump reaches a predetermined rate of flow of the fluid, the start valve assembly closes to circulate the fluid through said pump assembly.
It is to be understood that both the forgoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention as claimed. The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate an embodiment of the invention and together with the general description, serve to explain the principles of the invention.